Slidable mobile or portable electronic devices such as consumer electronic (CE) devices, mobile telephones, palmtops, and communicators are well known in the art and are available from a huge number of different manufacturers.
Especially, in the technical field of cellular telephones two main types of extendible devices are available, the flip cellular telephones, clamshell cellular telephones, or slidable cellular telephones such as the Nokia's Models N71 and N80. Sliding phones like the Nokia's Model N80 have typically a large display and an ITU-T keypad that becomes accessible when the front part of the two-piece housing is displaced upwards (forwards). Further form factors and extension mechanisms are also known in the technical field of cellular telephones. Exemplarily, rotatable/pivotable mechanisms such as implemented with Nokia's Model 7370 and mechanisms combining one or more of the above mentioned mechanisms e.g. Nokia's Model N90 have been developed.
However, the known approaches and designs of slidable mobile devices typically having a two-piece housing suffer from a common disadvantage in view of usability. The keypads and the display are arranged in different and typically substantially parallel planes due to their arrangement with different parts of the two-piece housing. Conventionally, keys destined for navigation through the user interface such as a multi-directional switch or joystick and/or keys for initiating/answering and/or ending a call are arranged with the part of the housing which comprises the display, whereas the more space requiring ITU-T keypad is arranged with the other part of the housing. For instance during inputting a telephone number and initiating the call set-up, a user has to actuate one or more keys of the ITU-T keypad as well as one or more keys arranged at the housing part comprising the display. Due to the thickness of the housing part comprising the display, the user may find the different levels at which the keys are arranged irritating or annoying.